Bearing and control assemblies for horizontally axised rotary mills



June 28, 1966 G. L. SAUNDERS 3,253,300

BEARING AND CONTROL ASSEMBLIES FOR HORIZONTALLY AXISED ROTARY MILLS Filed Sept. 25, 1964 4 Sheets-Sheet 1 5', 51g 1. fizzy/em,

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June 28, 1966 SAUNDERS AXISED ROTARY MILLS Filed Sept. 25, 1964 BEARING AND CONTROL ASSEMBLIES FOR HORIZONTALLY 4 Sheets-Sheet 2 INVENTOR.

AUNDE 3,258,300 SEMBLIES O HORIZONTALLY ROTARY M F R ILLS June 28, 1966 s BEARING AND CONTROL AS AXISED Filed Sept. 25, 1964 4 Sheets-Sheet 5 "75 j4\l m-- 25 g; i. .l a, III

G. L. SAUNDERS 3,258,300

June 28, 1966 BEARING AND CONTROL ASSEMBLIES FOR HORIZONTALLY AXISED ROTARY MILLS 4 Sheets-Sheet 4 Filed Sept. 25, 1964 INVENTOR.

United States Patent 3,258,300 BEARING AND CONTROL ASSEMBLIES FOR HORIZONTALLY AXISED ROTARY MILLS Guy L. Saunders, Toronto, Ontario, Canada, assignor to Nordberg Manufacturing Company, Milwaukee, Wis.,

a corporation of Wisconsin Filed Sept. 25, 1964, Ser. No. 399,162 8 Claims. (Cl. 308-73) This invention relates to hearing supports for ball mill trunnions and the like, and has for one purpose an improved shoe bearing support for a ball mill trunnion, which support includes a load sensor for measuring the load or charge in the mill.

Another purpose is a bearing arrangement of the type described including a plurality of bearing shoes positioned to support each end of the mill.

Another purpose is to provide a bearing shoe support of the type described which is adjustable.

Another purpose is a mill support including a plurality of shoe bearings, each of which may be supported on a load cell or sensor used in a mill control system.

Another purpose is a mill support of the type described in which the load cell can be removed.

Another purpose is a mill support which remains properly aligned at all times.

Another purpose is a mill support of the type described including means for easily changing the load cell.

Other purposes will appear in the ensuing specification, drawings and claims.

The invention is illustrated diagrammatically in the following drawings wherein: 1

FIGURE 1 is an end view of the shoe bearing assembly, showing a mill trunnion supported thereon,

FIGURE 2 is an enlarged sectional end view illustrating a single bearing shoe and its support means,

FIGURE 3 is a sectional side view of the shoe support illustrated in FIGURE 2,

FIGURE 4 is a sect-ion along plane 4-4 of FIGURE 1, and

FIGURE 5 is a section along plane 55 of FIG- URE 3.

The present invention relates to a support for the trunnions of a rotating mill, for example a ball mill or other type of grinding or material reduction mill, such as an autogenous mill. The trunnions are supported at each end on a structure of the type described and the mill may be driven in any conventional manner. A mill trunnion is indicated generally at 18. It has an outer peripheral surface 12 which moves on the bearing shoes to be described hereinafter.

The support for the trunnion may include a base 14 forming a housing and including sides 16, an inner wall 18 and an outer wall 20. As illustrated particularly in FIGURE 3, the inner and outer walls 18 and 20 may mount rings 22 and 24, respectively, with each of the rings having grooves for mouting sealing members or the like 26 and 28. The sealing members 26 and 28 are positioned to be contacted by side members 38 and 32 on trunnion 10. Grooves 34 and 36 may be formed on the inside edges of the side members 30 and 32, respectively, with these grooves preventing oil from the shoe bearings from passing to the outside. Side member 32 is removable to facilitate changing of the bearing shoes.

Within the housing of the trunnion support are a plurality of frames or supports, each of which mounts a bearing shoe. For example, as shown in FIGURE 1, there are frames 38, 40 and 42, each of which supports a bearing shoe. Frame 40 is seated on the bottom of the housing, whereas frames 38 and 42 are supported on angular columns 39 and 43. The frames 38, 40 and 42 are identical and only one will be described in detail here- "ice in. The housing for the supports may be completed by windows 44 and 46 which are positioned so that the interior of the structure may be visible from the outside.

Turning to FIGURE 2, a bearing shoe 50 has an outer arcuate or curved surface 52 which is designed to match the shape of the trunnion surface 12. A spherical spacer 54 has a projection 56 which fits into a relatively shallow channel or the like 58 in the bottom of the bearing shoe 50 to interconnect these two parts. The lower surface of the spacer 54 has a spherical shape to mesh with an upwardly concave, generally spherical surface 60 formed at the top of a spherical socket 62. The spherical surfaces maintain alignment of the bearing surface 52 with the trunnion surface 12. A guide member 64 contains the socket member with the guide member 64 having outstanding flanges 66 which seat on frame portions 68 within the housing. The frame portions 68 may be supported by upwardly extending frame members 70 on each side of the bearing support structure. The lower end of the guide member 64 may have a threaded area 72 which is in mesh with a threaded area 74 on an adjusting nut 76. The adjusting nut may be moved up and down within guide 64 to raise and lower socket member 62 to thus raise and lower the bearing shoe 50. The upper end of the guide member 64 may have flanges 78 which are 7 positioned to mate with grooves 80 on the bottom of the shoe 50 so that the shoe 50 may seat upon the guide member 64 rather than upon the socket member 62 as shown in FIGURE 2 when adjusting nut 76 is lowered.

A generally central bore 82 is formed in the adjusting nut 76 and a support column 84 extends upwardly through the bore 82 and is screw-threaded into a threaded bore 86 in the socket member 62. The column support 84 has a tool engaging surface 88 at its lower end and the column support is seated on the upper end 90 of a load cell or load sensor or strain gauge 92. The strain gauge 92 may be fastened by screws or the like 94 to a plate 96 which is in turn fastened by screws 98 to the base 14. The plate 96 may fit in a groove 100. After removal of screws 98 the strain gauge or load cell 92 may be slid in and out of the structure when the load cell is no longer supporting the bearing shoe.

It is necessary in a structure of the type described to provide lubrication to the surfaces of the bearing shoe which support the trunnion. It is also advantageous to provide a high pressure oil for use before the mill is started and a lower pressure oil for use when the mill is rotating. A high pressure oil line is indicated at 102 and is connected to a passage 184 in shoe 56 with the passage 10'4 opening into an upwardly extending passage 186, which feeds oil into a somewhat concave recess 108. Low pressure oil is supplied through a line and a connection 112 to a groove 113 running almost the full width of the bearing shoe upper surface. The housing itself is preferably used as the oil sump, and it receives the oil running off the bearing shoes, although it could be otherwise.

A bracket or the like may be mounted on each side of the frame on top of flanges 122 which may be inwardly directed extensions of side 16. Each bracket 120 pivotally mounts a pair of guide shoes 124. See FIG- URE 4. The outer bearing surfaces 126 of shoes 124 bear against the inner peripheral surfaces 128 of side members 30 and 32 which extend in spaced relation about the trunnion 10. The space between the side members is suificient to accommodate the guide shoes as well as the bearing shoes. The guide shoes maintain proper alignment between the trunnion and bearing shoes during rotation.

-The use, operation and function of the invention are as follows:

The trunnion support structure shown herein is designed for use on material reduction mills, for example ball mills or autogenous grinding mills of large diameter. In large mills of this type the support of the trunnions may become a problem. As shown herein, each trunnion is supported by a plurality, for example three, shoe bearings which are pivotally mounted in spherical sockets. The load bearing surfaces of the shoes are provided with lubricant, for example oil or the like, which makes for a smoothly turning trunnion. Both high and low pressure oil may be supplied.

Each of the shoe supports includes a load sensor or strain gauge, which may be of the type to provide an electric signal indicative of the superimposed load. These electric signals can be used to perform a control function for regulating the material feed to the mill. Other types of load sensors, for example ditferential transformer, may be practical and the output may be an electric signal or a hydraulic signal.

As shown in detail in FIGURES 2 and 3, each of the shoe supports are adjustable to place the load of the trunnion, through the bearing shoes, either on the load sensors or on a portion of the housing frame The adjusting nuts 76 may be moved upwardly so that the load is transmited from the bearing shoe 50 through spherical spacer 54, to spherical socket 62, to the adjusting nut 76, through the threaded portions 74 and '72, to the socket guide 64 and thence to the portion of the frame 68. On the other hand, each adjusting nut 76 may be backed down to the .point where the load is transmitted from the bearinlg shoe 50 to the spherical socket 62, to the mating threads 86 to the support column 84 and then to the load sensor 92.

When the load is transmitted to the frame, support column 84 can be turned upward to provide clearance above the load sensor 92. Bolts d8 may then be removed and the load sensor 92 may be removed and replaced.

If it is desirable to remove spherical spacer 54, spherical socket 62, support column 84 or adjusting nut 76, Sup port column 84 is turned upward until maximum upward adjustment is achieved. Then load sensor 92 is removed as above and load column 84 is then turned downward until threads 86 are disengaged. Adjusting nut 76 is turned downward until the threads 72 and 74 disengage. The spherical socket 62 and spherical spacer 54 may then be removed.

Both the column support 84 and the adjusting nut 76 may be rotated to place the load of a bearing shoe on either the load cell or on the frame support. There is a tool engaging surface on the column sup-port 84 so that this member may be turned down until the load bears on the load cell or strain gauge. The adjusting nut 76 is used to raise the bearing shoe up off of the guide 64 and to place it on the socket member 62.

Of importance is the fact that when the shoes are supported by guides 64, both socket members 62, the spherical spacers 54 and the load cells can be removed and replaced.

Whereas the preferred form of the invention has been shown and described herein, it should be realized that there are many modifications, substitutions and alterations thereto within the scope of the following claims.

I claim:

1. In a shoe bearing assembly for mills and the like, a base, shoe supporting means on the base including fixed frame portions, a socket guide mounted on said frame portions, a socket member adjustable in said guide for movement toward and away from the axis of the mill, an adjusting member in screwathreaded relation with the socket guide for movement in said guide toward and away from the axis of the mill, a column support adjustably positioned in said socket member for movement toward and away from the axis of the mill, a load sensor on said base and positioned to support said column support, the socket member having an upwardly concave, generally spherical socket, a spherical spacer in said socket having an outwardly convex, generally spherical surface opposed to the upwardly concave surface of the socket, and a bearing shoe mounted on said spherical spacer.

2. The structure of claim It further characterized in that said column support is screw-threaded into said socket member for movement toward and away from said load sensor.

3. The structure of claim 2 further characterized in that the relative positions and sizes of said fixed frame portions, said adjusting member, and said column support are such that the weight on the bearing shoes is supported either by said fixed frame portions, or by said load sensor.

4. In a shoe bearing assembly for mills and the like, a bearing shoe, shoe supporting means [for the bearing shoe, a base having frame portions positioned to support said shoe supporting means, a load sensor on the base positioned to support said shoe supporting means, said shoe supporting means being adjustable so that said bearing shoe is supported either from the frame portions or from the load sensor.

5. The structure of claim 4 further characterized in that said shoe supporting means includes a socket guide mounted on said frame portions, and a socket member adjustable in said socket guide for movement toward and away from the axis of the mill.

6. The structure of claim 5 further characterized by and including an adjusting member screw-threaded into the socket guide and positioned to move said socket member toward and away from the axis of the mill.

7. The structure of claim 6 further characterized by a column support adjustably mounted in said socket member and positioned to seat on said load sensor.

8. In a shoe bearing assembly for mills and the like, a plurality of pivotal bearing shoes, shoe supporting means for each bearing shoe, a base having frame portions positioned to support each of said shoe supporting means, a plurality of load sensors, one for each bearing shoe, each load sensor being positioned on the base and being positioned to support one of said shoe supporting means, said shoe supporting means each being adjustable so that said bearing shoes are supported either on the frame portions or on the load sensors.

References Cited by the Examiner UNITED STATES PATENTS DAVID J. WILLIAMOWSKY, Primary Examiner.

FRANK SUSKO, Examiner. 

1. IN A SHOE BEARING ASSEMBLY FOR MILLS AND THE LIKE, A BASE, SHOE SUPPORTING MEANS ON THE BASE INCLUDING FIXED FRAME PORTIONS, A SOCKET GUIDE MOUNTED ON SAID FRAME PORTIONS, A SOCKET MEMBER ADJUSTABLE IN SAID GUIDE FOR MOVEMENT TOWARD AND AWAY FROM THE AXIS OF THE MILL, AN ADJUSTING MEMBER IN SCREW-THREADED RELATION WITH THE SOCKET GUIDE FOR MOVEMENT IN SAID GUIDE TOWARD AND AWAY FROM THE AXIS OF THE MILL, A COLUMN SUPPORT ADJUSTABLY POSITIONED IN SAID SOCKET MEMBER FOR MOVEMENT TOWARD AND AWAY FROM THE AXIS OF THE MILL, A LOAD SENSOR ON SAID BASE AND POSITIONED TO SUPPORT SAID COLUMN SUPPORT, THE SOCKET MEMBER HAVING AN UPWARDLY CONCAVE, GENERALLY SPHERICAL SOCKET, A SPHERICAL SPACER IN SAID SOCKET HAVING AN OUTWARDLY CONVEX, GENERALLY SPHERICAL SURFACE OPPOSED TO THE UPWARDLY CONCAE SURFACE OF THE SOCKET, AND A BEARING SHOE MOUNTED ON SAID SPHERICAL SPACER. 